I'm sure many of you regulars have heard this many times before (I'm new to the forum so please be gentle with me!), but my wife bought me a an Oris Big Crown Pointer Date for my birthday and when I found out she bought it on Ebay my suspicions were immediately raised, especially as the seller seems to sell a few of these (and other brand) watches - I'm reluctant to name the seller in case it is genuine.
I really have no idea how to tell if it's genuine - it seems to keep time fine and the date pointer works ok (have adjusted with no problem). The movement looks fine to my (very) untrained eye but I can't see any markings on the movement itself - having said that I haven't removed the back (and am reluctant to do so as I'm far from being competent never mind an expert!). The crown does state ORIS but there is scratching around the name which again makes me suspicious.
Can anyone give me any guidance on this? Am I just being paranoid?